The present invention relates to a fluid-operated wrench for tightening or loosening threaded connectors.
Fluid-operated wrenches of the mentioned general type are known in the art. Some of these fluid-operated wrenches are disclosed, for example in my U.S. Pat. Nos. 4,079,641 or 4,386,727, or in the DE-OS No. 3,113,482. These hydraulic wrenches have a wrench body provided with a cylinder-piston unit, and a link connected with the body and arranged to engage a polygonal head of a threaded connector. When the body abuts against an adjacent object, such as for example an adjacent nut, a flange or the like. and the cylinder-piston unit is actuated. the link is turned by the cylinder-piston unit and, in turn, turns the threaded connector for tightening or loosening the latter. In all known fluid-operated wrenches the link extends transverse to the cylinder-piston unit. Because of this the wrench is relatively complicated to manufacture, and the link is relatively high and therefore poses some problems in limited clearance areas. In the wrenches which are used as limited clearance-type tools, the thickness of a ratchet which is mounted on the link makes it impossible to use lever plates and housing plates in addition. When only lever plates are used and when the lever plates have to be moved around the center of a ratchet axis, the mechanism become extremely complicated.